Fastener advance delay for fastener driving tool

Abstract

A nailer includes a power source including a piston reciprocating within a cylinder, a driver blade secured to the piston for common movement relative to a nosepiece, a magazine connected to the nosepiece for feeding fasteners sequentially for being driven into a workpiece by the driver blade, a delay mechanism operatively associated with the magazine and configured for engaging a second fastener and delaying advancement of the subsequent fastener to the nosepiece until the driver blade returns to the pre-firing position after driving a leading fastener.

The invention claimed is: 
     
       1. A nailer, comprising:
 a power source; 
 a driving element in communication with said power source for creating reciprocal movement of said driving element relative to a nosepiece; 
 a magazine connected to said nosepiece for feeding fasteners sequentially for being driven into a workpiece by said driving element; and 
 a fastener delay mechanism operatively associated with said magazine and configured for engaging a subsequent fastener and delaying advancement of the subsequent fastener to said nosepiece until said driving element returns to a pre-firing position after driving a first fastener; 
 said nailer includes a control program, and said delay mechanism is constructed and arranged to be controlled by said control program to energize said delay mechanism for a predetermined period of time; and 
 said delay mechanism including a reciprocating plunger mounted transverse to a direction of movement of the fasteners in said magazine, being arranged for engaging a strip of fasteners between fasteners of the strip, and when energized, blocks movement of the fastener toward said nosepiece under control of said control program. 
 
     
     
       2. The nailer of  claim 1  wherein said delay mechanism is an electromagnetic solenoid connected to said control program and having said reciprocating plunger which, when said solenoid is energized, blocks movement of the fastener toward said nosepiece for a predetermined period of time. 
     
     
       3. The nailer of  claim 2  wherein said predetermined time is on the order of 100 msec. 
     
     
       4. The nailer of  claim 1  wherein said driving element is a driver blade attached to a piston, and said nailer includes a piston position indicator switch, and said delay mechanism is an electromagnetic solenoid connected to said switch and being activated once said piston moves from said pre-firing position upon an ignition event, said solenoid having said reciprocating plunger which, when said solenoid is energized, blocks movement of the fastener toward said nosepiece until said piston position actuates said switch to indicate that the piston has reached said pre-firing position. 
     
     
       5. The nailer of  claim 1  further including a control program connected to said delay mechanism and including a function for energizing said delay mechanism until a specified time corresponding to when said driving element reaches the pre-firing position. 
     
     
       6. The nailer of  claim 1  wherein said delay mechanism is operated mechanically by direct contact with said driving element, such that, after ignition, the driving element moving toward the fasteners activates said delay mechanism, which remains activated until said driving element is retracted to said pre-firing position. 
     
     
       7. A nailer, comprising:
 a power source; 
 a driving element in communication with said power source for creating reciprocal movement of said driving element relative to a nosepiece; 
 a magazine connected to said nosepiece for feeding fasteners sequentially for being driven into a workpiece by said driving element; and 
 a fastener delay mechanism operatively associated with said magazine and configured for engaging a second fastener and delaying advancement of the second fastener to said nosepiece until said driving element returns to a pre-firing position after driving a first fastener, 
 wherein said nailer includes a control program, and said delay mechanism is constructed and arranged to be controlled by said control program to be energized for a predetermined period of time, and said delay mechanism being triggered by the position of said driving element; and 
 wherein said nailer includes a piston position indicator switch, and said delay mechanism includes an electromagnetic solenoid connected to said switch and being activated once said piston moves from said pre-firing position, said solenoid mounted for engaging a strip of fasteners between first two fasteners of the strip, and having a reciprocating plunger which, when said solenoid is energized, blocks movement of the fastener toward said nosepiece until said piston position actuates said switch to indicate that the piston has reached said pre-firing position.